In the field of medical navigation, in which, for example, surgical instruments are located, positionally tracked and displayed on an image display system (monitor) together with patient structures (e.g., for image-assisting the treatment), it is often necessary and advantageous to unambiguously identify the instruments. This is particularly true when working with so-called pre-calibrated instruments, i.e., instruments whose external shape and function have already been stored in advance in a data memory of the medical navigation system. During medical navigation, these instruments can be automatically identified. Based on this identification, the navigation system has enough information concerning the instrument to correctly navigate the instrument.
WO 2004/001569 A2, for example, has already proposed using a separate barcode reader to identify such instruments. This has the disadvantageous effect that the instruments have to be guided to the barcode reader prior to use, which exhibits a relatively small visual range. Naturally, additional costs also arise for acquiring, handling and maintaining the barcode reader.